Even outside of the legal complications that could arise.....would you really want your extremely expensive NFA item to be sitting in an evidence locker for an untold amount of time when a $300-$500 shotgun or rifle would have done the job just fine?

No disrespect intended, but i never understand this line of reasoning. If I use an expensive firearm to save my life, and I have to part with it temporarily or even permanently, I will have zero regrets.

In the case of a suppressor, my hearing is worth exponentially more than the cost of any suppressor, and even more so because I am a lifetime music professional.

Any indoor gunfire, but especially rifles and shotguns, can do permanent and severe damage to one's hearing. Young children with undeveloped ears are even more susceptible to hearing loss. I would hate to have to choose between my life and my hearing (or a loved one's life or hearing). But losing money (the cost of that equipment) wouldn't even be a consideration.